Beam-compass



(No Model.)

J. H. HURLEY. BEAM COMPASS.

No. 499,999. Patented June 20, 1893.

Wi UVWo/apo UNITED STATES PATENT OFFICE.

JAMESH. HURLEY, OF HARTFORD, CONNECTICUT.

BEAM-COMPASS.

SPECIFICATION forming part of 'Letters Patent No. 499,999, dated June 20, 1893.

Application filed February 13, 1892- Serial No. 421,466. (No model.)

To all whom it may concern.-

Be it known that 1, JAMES H. HURLEY, of Hartford, in the county of Hartford and State of Connecticut, have invented certain new and usefulImprovements in Beam-Compasses, of which the following is a full, clear, and exact description, whereby any one skilled in the art can make and use the same.

The object of my invention is to provide a beam compass that shall be light,durab1e,accurate and of comparatively cheap construction and to this end my invention consists in the details of the several parts making up the construction as a whole and in the combination of such parts as more particularly hereinafter described and pointed out in the claims.

Referring to the drawingsz-Figure 1 is a detail side view of a beam compass embodying my invention. Fig. 2 is a detail view in lengthwise section of an end part showing the feed screw in its socket and on enlarged scale.

In the accompanying drawings the letter a denotes the compass beam thatis made of a hollow tubing angular in cross section and preferably square so that two of the angles will lie directly opposite each other along the beam. 011 this beam is fitted the adjustable points I) 0. One of these points I) has a body part b with a'socket for the clamp screw d and the end of the socket piece extends beyond the end of the beam and forms a yoke embracing the end. Through the cross bar d of this yoke a feed screw passes and it extends into a threaded socket ct in the end of the bar, a plug being secured in the end of the bar to provide for such socket. The feed screw 6 has a head e that is made integral therewith or secured to it by brazing. This forms the micrometer feed device and provides for a finer adjustment of the relative distances between the two points in setting the tool in use. The sliding point 0 is provided with a clamp screw 0' extending through athreaded socket and adapted to bind upon the edge of the bar while the lower end of the point is provided with an adjustable arm supporting a pencil. This arm f is clamped to the shank of the socket piece or to the point by means of a clamp screw f. The two adjustable points on this beam compass are both placed so as to lie in the same plane and the angular shape of the bar enables the points that are fitted to socket pieces having sockets through them that'fit closely upon the bar to be readily moved along the latter without throwing them out of the plane that passes through the opposite edges of the beam.

This compass bar is made of a piece of hollow tubing angular in cross section and is extremely light and rigid besides possessing the peculiar advantage of having the edges in a suitable location with reference to each other to enable the compass .points to be movable and yet kept in substantially the same plane in making the several adjustments.

I claim as my invention- 1. In a beam compass in combination with an angular tubular compass bar having edges diametrically opposite each other, a compass point borne in the socket ad justably secured to the bar by means of a clamp screw, a feed device consisting of a yoke extending from the socket piece across the end of the barand supporting a rotary feed screw with a threaded end extending into the socket in the end of the compass bar, and an adjustable point having clamping means, all substantially as described.

2. Ina beam compass in combination with an angular tubular compass bar having edges diametrically opposite each other, a compass point borne in the socket adjustably secured to the bar by means of a clamp screw, a feed device consisting of a yoke extending from the socket piece across the end of the bar and supporting a rotary feed screw with a threaded end extending into the socket in the end of the compass bar, an adjustable point also located on the compass bar and having clamping means for securing it to said bar and the adjustable marking point located on and hav- 7 ing means for clamping it to said marking point, all substantially as described.

JAMES H. HURLEY. Witnesses:

CHAs. L. BURDETT, A. B. JENKINS. 

